Electric-arc lamp.



Patented July l7, |9oo.

8. BEBGMANN.

ELECTRIC ARC LAMP.

(Application filed Mar. 18, 1899.)

(No Model.)

7 I wnuzssss: I

NITED STATES PATENT OFFICE.

SIGMUND BERGMANN, OF NEW YORK, N. Y., ASSIGNOR TO THE GENERAL INOANDESOENT ARC LIGHT COMPANY, OF NEW YORK.

ELEQTRlC-ARC LAM P.

- SPECIFIGATION forming part Of Letters Patent NO. 653,785, dated July 17, 1900.

Application filed March 18, 1899. Serial No. 709,610. (No model.)

To all whom it may concern: 7

Be it known that I, SIGMUND BERGMANN, a citizen of the United States, residing at New York city, county and State of New York, have invented new and useful Improvements in Electric-Arc Lamps, of which the following is a specification.

My invention relates to electric-arc lamps of the type which employ an inner arc-inclosing globe; and it consists in a support for such globe which has for its object to compensate for the expansion and contraction of the metallic portions of the lamp between which the globe is located, and thus prevent the introduction of external air to the interior of the globe; also, to provide means for readily introducing and removing the inclosing globe.

The accompanying drawing, which is a front elevation and partial horizontal section of the lower portion of a lamp, will serve to illustrate my invention.

1 represents the base of the lamp, supporting the regulating mechanism, (not shown,) and 2 one of two rods dependingfrom the base of the lamp and carrying the annular plate 3. Secured to the bottom of this plate by screws or othersuitable means and insulated therefrom in any suitable manner-for instance, by a sheet of mica, (not shown)is a second, but thin, annular plate 4, having its interior circumference turned upward and inward to form a seat 5, having the shape of a flattened cone. Manifestlyinstead of forming the seat in the second annular plate it may be formed in the plate 3, in which case the second annular plate may be dispensed with. I, however, prefer to use it, as, owing to its being made of thin metal,it is not so good a conductor of heat as the heavier first plate.

Depending from the plate 3 are the rods 6.

7 is a yoke for supporting the inner arc-inclosing globe S.

9 is a gas-cap provided with an annular ring 10, which rests on the top of the globe depending portion 11, which is inserted into the globe and upper projecting portion 12, shaped to correspond to the seat 5 in the plate 4, I a

13 are helical springs or other suitable elastic-tension device which will exert an upward and the annular plate for the seat, as well as Y the depending rods which support the globe, 6o become heated, and as a result, if the yoke 7 is rigidly attached to the, depending rods,

which is the usual practice, the top of the gas-cap, owing to the extension of the rods 6 by heating,will be moved downward and leave the seat in the annular plate and an opening thereby result, through which atmospheric air may enter the inner globe.

In my improved device the springs exerta constant tension upon the yoke 7 in an upward direction, so that the top of the gas-cap is maintained in its seat and the globe pressed upward against the ring 10, the effect of which is to maintain the body and quality of gas in the interior of the globe constant, and so decrease the consumption of the carbons. In practice I have found that a lamp in which carbons usually burn one hundred hours when provided with my improvement will burn, approximately, two hundred hours.

I do not broadly claim a construction in which the inclosing globe and its gas-cap is maintained in contact with an annular plate by means of an elastic-tension device.

IIavin g thus described my invention, I claim-- In an electric'arc lamp, the combination with an arc-inclosing globe, of a gas-cap, an annular plate provided with an independent seat for the gas-cap made of thin metal, rods depending from said plate, a yoke for sup porting said globe, and an elastic-tension de vice interposed between said plate and said yoke.

In testimony whereof I affix my signature 9 5 in the presence of two witnesses.

SIGMUND BERGMANN.

lVitnesses:

F. H. Fos'rna, ALFRED A. J ANssEN. 

